A metal security door is disclosed in U.S. Pat. No. 4,663,950 and it is hingedly mounted onto a metal frame that is secured around a doorway of a building. A metal flap member is secured onto the metal frame of the security door along the section of the door frame containing the door latch and lock. The flap member extends across -the doorway metal frame when the security door is in a closed and locked position. The flap member protects the door latch and lock thereby preventing access to them via a hacksaw or chisel to break open the security door.
While the protective flap member protects against the use of hacksaws, chisels or the like, it has been found that it serves as a means for engagement by a crowbar or other prying member for prying open the security door wherein the crowbar or prying member engages the flap member and the door frame and upon pressure being applied to the crowbar, the flap member serves to pry the door open or the flap member can be bent away from its normal position to enable access to the door lock.
It is therefore a primary object of the present invention to provide mean to prevent use of the protective flap member on a security door as a prying member for prying open the security door or to enable the flap member to be bent away from its normal position. The flap member is also provided with means that engages the door frame when a prying member is inserted between the door frame and the door thereby preventing twisting of the door frame and the frame of the door so as to obtain access to the lock or to move the lock free of the door frame.